Researching and writing about drug addiction and personal loss sounds not only challenging, but very depressing. What kept you going as you were developing the book?

Guilt. When my brother died, I was shell-shocked. I felt a strong sense that I had failed him. Pat was 10 years younger than me, and our dad was sick with cancer for most of Pat’s life (he died when I was 19 and Pat was nine), so I spent a lot of time babysitting Pat when we were younger, and there was a maternal aspect to our relationship. But I also tried to foster openness and honesty between us, which is why I didn’t understand the secrecy of his addiction. Hiding is a part of addiction; no one wants those who love them to know the depths of their darkness. I didn’t know that at the time, so I felt that Pat was either making stupid choices or actively trying to hurt me—sometimes both. And because of that misperception, I was angry with him. I had no experience with addiction and I certainly didn’t know about the link between painkillers and heroin. I ended up saying things to him like “just stop doing drugs,” as if it were something he was doing for fun. He wasn’t. His downfall was hard and fast, and shocking in the context of our family. Of course we’d had tragedy with the loss of our dad, we weren’t perfect, but we loved each other and lived in a great community where this type of thing didn’t happen.